diff --git a/challenges/metagrating/leaderboard.txt b/challenges/metagrating/leaderboard.txt
index 6d93764..5f86a9d 100644
--- a/challenges/metagrating/leaderboard.txt
+++ b/challenges/metagrating/leaderboard.txt
@@ -1,5 +1,5 @@
 path=challenges/metagrating/solutions/230803_jiaqui-jiang_00.csv, eval_metric=0.955985497924281, minimum_width=5.0, minimum_spacing=5.0, binarization_degree=1.0
 path=challenges/metagrating/solutions/230803_jiaqui-jiang_01.csv, eval_metric=0.9352761580405694, minimum_width=5.0, minimum_spacing=1.0, binarization_degree=1.0
 path=challenges/metagrating/solutions/230803_jiaqui-jiang_02.csv, eval_metric=0.9497323504720799, minimum_width=5.0, minimum_spacing=8.0, binarization_degree=1.0
-path=challenges/metagrating/solutions/230803_oskooi_00.csv, eval_metric=0.9124907066625562, minimum_width=7.0, minimum_spacing=6.0, binarization_degree=1.0
+path=challenges/metagrating/solutions/230803_oskooi_00.csv, eval_metric=0.9124907066625562, minimum_width=4.0, minimum_spacing=6.0, binarization_degree=1.0
 path=challenges/metagrating/solutions/230803_oskooi_01.csv, eval_metric=0.8299873328887453, minimum_width=7.0, minimum_spacing=3.0, binarization_degree=1.0
diff --git a/src/invrs_leaderboard/utils.py b/src/invrs_leaderboard/utils.py
index 0dcec06..2f6ae4a 100644
--- a/src/invrs_leaderboard/utils.py
+++ b/src/invrs_leaderboard/utils.py
@@ -181,7 +181,9 @@ def compute_length_scale(params: Any) -> Tuple[Optional[int], Optional[int]]:
         arrays = leaf.array.reshape((-1,) + leaf.shape[-2:])
         arrays = arrays > (leaf.lower_bound + leaf.lower_bound) / 2
         for arr in arrays:
-            width, spacing = imageruler.minimum_length_scale(onp.asarray(arr))
+            width, spacing = imageruler.minimum_length_scale(
+                onp.asarray(arr), periodic=leaf.periodic
+            )
             min_width = width if min_width is None else min(width, min_width)
             min_spacing = spacing if min_spacing is None else min(spacing, min_spacing)